Experimental Study On The Physical Mechanical Properties Of Heavy Metal Contaminated Expansive Soil In Nanyang

In recent years,with the rapid growth of GDP and the improvement of people's living standard,the soil pollution situation is becoming more and more serious,heavy metal contaminated soil has brought serious social problems.For heavy metal contaminated expansion soil caused by all kinds of practical problems and physical mechanical properties,this article selects the heavy metal ions(Pb²⁺,Zn²⁺,Cu²⁺)and Nanyang expansive soil as the research object,using the basic soil tests,swelling tests,and cyclic load consolidation test,mainly studied heavy metal contaminated expansion soil physical mechanical properties and consolidation characteristics of the change and the influence of different concentration of heavy metal ions on expansive soil swelling,in order to solve the engineering practice of the problems of expansive soil heavy metal pollution to a certain extent,the theory of support.Themain research contentsand results areas follows:In laboratory soil tests,analysis is not pollution of expansive soil and expansive soil heavy metal pollution of the differences between physical and mechanical properties,on this basis,the study of different species,different concentration of heavy metal ions on the effect of expansive soil physical and mechanical properties.The results show that the soil density and pore ratio of expansive soil in Nanyang are increased with the pollution of heavy metals(Pb²⁺,Zn²⁺,Cu²⁺),andthe indexofliquid,plasticandshear strength decreases.Swelling experiment was carried out by different initial moisture content and initial dry density and heavy metal ions(Pb²⁺,Zn²⁺,Cu²⁺)content of no load expansion deformation test,study of Nanyang expansive soil without load rate and initial moisture content and initial dry density and the relationship between the content of heavy metal ions,reveal the heavy metals(Pb²⁺,Zn²⁺,Cu²⁺)pollution of expansive soils expansive properties change rule.The experimental study shows that the non load expansion rate of Nanyang expansive soil is linear with the initial water content and initial dry density.Under the same condition,the influence degree of heavy metal ions(Pb²⁺,Zn²⁺,Cu²⁺)on expansibility of expansive soil from high to low is Pb²⁺,Cu²⁺,Zn²⁺,and theexpansibilityofexpansivesoil is enhanced.Through standard consolidation test and cyclic loading conditions consolidation test,study different types,different concentration of heavy metal ions and different cyclic loading waveform features of Nanyang expansive soil consolidation effect.The study shows that the compressibility of expansive soil is enhanced by heavy metal pollution.Under cyclic loading conditions,the compressibility of heavy metals(Pb²⁺,Zn²⁺,Cu²⁺)polluted expansive soil increases withtheincrease ofheavy metalion concentration.